Couples with severe male factor infertility (low concentration or motility, high abnormalities or positive anti-sperm antibody binding), or those who have had repeatedly low or no fertilisation with conventional IVF, are offered Intracytoplasmic Sperm Injection (ICSI). This treatment has been a major step forward in assisted reproduction technology. In simple terms, ICSI is an extension of IVF and works by assisting the sperm to penetrate the egg.
Following egg collection, the mature eggs are specially treated to remove the cumulus cells surrounding them. A single sperm is selected and drawn up into a very fine, specially prepared glass needle. The embryologist then injects this sperm directly into the egg, under microscopic control, using specialised instruments.
Once injected, the eggs are placed in an incubator until the following morning, when they are examined for signs of fertilisation (Day One). Despite ICSI being used to increase the chance of fertilisation, unfortunately, it cannot guarantee it.
In some cases, men may not have any sperm in the ejaculate, known as azoospermia. There are two types of azoospermia, obstructive and non-obstructive. Obstructive azoospermia is caused by blockage or absence of the vas deferens (the duct that transports sperm from the testicle to the outside). In such cases, sperm may be retrieved surgically and used with ICSI for fertilising the eggs.
In some cases of non-obstructive azoospermia, if required, a specialist urologist may be able to retrieve very small amounts of sperm directly from the testicle using microscopic surgical sperm retrieval techniques.